There's a line drawing, one external and one internal view of a mock-up. I found the "beak" really amusing. Would they have called it "The Penguin"? The external shape of the cabin reminds me of an early tank turret.

Any idea about the purpose of the "penguin beak"? It's not immediately obvious.

From the text (quoted?) in the description of the images:

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Docking was to have been achieved by a probe and drogue mechanism. The method was to allow the crew to take advantage of good visibility and not have to change positions. Controls, displays and cues would not change during docking. Once the probe was aligned with the drogue, it would be locked in place, and the LEM rotated 90 degrees for final mating and crew transfer.

So, I think the "beak" is a part of the docking mechanism and it's supposed to move on its "rail" to align the hatches and complete the docking. It's one of the reasons why the top of the lander reminded me of a tank turret - it resembles the mechanisms used to change gun elevation.

There's a line drawing, one external and one internal view of a mock-up. I found the "beak" really amusing. Would they have called it "The Penguin"? The external shape of the cabin reminds me of an early tank turret.

I'll try to dig up more information and/or pictures later.

Reading the post and then clicking on the link, it looked a lot less ridiculous than I was expecting

My first thought upon seeing the beak was that it looks like a giant on/off switch. Which of course it isn't.

Another interesting point is that the RCS thrusters are asymmetric - the different units point in different directions.

I was looking at that. They can do an uncoupled yaw maneuver, but I don't see how they can do an uncoupled pitch or roll, i.e., one that doesn't also induce translation. There's also no way to do a Y-axis translation (using the same coordinates as the Grumman LM). There is, however, full redundancy for each thruster that does exist. That wasn't true for the Grumman LM, which would have had to use uncoupled maneuvers.

There are three more rocket engines mounted on the underside of the ascent stage that are hidden when it is still attached to the descent stage, which consists only of tankage. So the same engines would be used for both ascent and descent powered flight.

The two smaller engines on the side would have made it possible, with proper balancing of impulse, to do uncoupled roll maneuvers but I still don't see how to do an uncoupled pitch maneuver.

Overall I think NASA made the right choice selecting the Grumman design, but it also got changed a lot during development. Who knows what this one would have become if it had been selected. The use of the same engines for descent and ascent is an interesting way to save weight, but those extra medium-sized (backup?) engines might have used up much of the savings.

Was the plan to go out through the top and down a rope ladder? Or not to do EVAs at all? Or maybe they hadn't worked out that detail yet...

I've often wondered why Grumman chose to go with separate descent and ascent engines. It always seemed to be a lot of extra mass that you could shed just by leaving a hole in the bottom of the descent stage as in this design. I have read Kelly's Moon Lander but I don't recall his addressing that specific design choice.

Overall I think NASA made the right choice selecting the Grumman design, but it also got changed a lot during development. Who knows what this one would have become if it had been selected. The use of the same engines for descent and ascent is an interesting way to save weight, but those extra medium-sized (backup?) engines might have used up much of the savings.

The description of the images in the original Flick gallery calls them "standby thrust chambers":

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Convair's proposed vehicle featured a single throttleable main engine backed by two standby thrust chambers. It was to be a partially staged configuration with a side-by-side crew arrangement and a probe-drogue docking mechanism. The lower structure held the descent tankage, which was to be depressurized 15 seconds prior to touchdown. The depressurized tankage, along with the crushable vehicle skirt, were to offer a back-up to the landing system in the event of a landing accident.The engines were protected against landing damage through use of a crushable main engine nozzle skirt and the placement of the standby engines above the descent tankage.

Reading the post and then clicking on the link, it looked a lot less ridiculous than I was expecting

I agree. Whenever I think Convair, the first thing that pops in my head are Delta Darts/Daggers and Hustlers.

B-36's.

Lovely beast! They had gear-reduction between the engine & props to keep the blade tips sub-sonic, and this gave them a very distinctive sound. Time to watch Strategic Air Command, starring Jimmy Stewart, again!